Pigmented yarn



nited States Patent Ofliace 2,839,420 Patented June 17, 1958 PIGMENTED YARN Alden Wo Hay, Madison, N. J assignor to Celanese Corporation of America, New York, N. Y., a corporation of Delaware No Drawing. Application July 7, 1955 Serial No. 520,629

11 Claims. (Cl. 106-193) This invention relates to a pigmented yarn and relates more particularly to a black pigmented yarn having a deep black shade.

An important object of this invention is to provide a pigmented black yarn which may be converted into a fabric having a deep black shade.

Other objects of this invention will be apparent from the following detailed description and claims.

The production of a black yarn by the spinning of a filament-forming material containing carbon black has long been known. To obtain a deep black shade, it is necessary to incorporate a fairly high proportion of carbon black into the filament-forming material which appreciably increases the expense of the yarn and also tends to reduce the tenacity and other physical properties thereof.

According to the present invention, a black yarn having a deep black shade is produced by incorporating into the said yarn carbon black together with a small proportion of an inert White pigment, preferably titanium dioxide. Surprisingly enough, the addition to the yarn of titanium dioxide in small amounts, which addition would normally have been expected to produce a grey shade, actually improves the depth of the black shade. As a result, it is possible to obtain a black yarn having a given shade with the use of a smaller proportion of carbon black, or, if desired, to obtain a yarn having a deeper black shade with a given proportion of carbon black.

This invention is applicable generally to the production of pigmented yarn from filament-forming material of any type. For example, it maybe employed in the production of yarn from organic acid esters of cellulose such as cellulose acetate, cellulose propionate, cellulose butyrate, cellulose acetate propionate and cellulose acetate butyrate. It may also be employed for the production of regenerated cellulose yarn by the viscose or cuprammonium process. Other pigmented yarns to which the process of this invention are applicable are those prepared from polyamides, polyurethanes, polyaminotriazoles, polyesters, polymers and copolymers of vinyl chloride, polymers and copolymers of vinylidene chloride, and the like.

In carrying out this invention, there is incorporated into the filament-forming material a proportion of carbon black in finely dispersed form. The precise quantity of carbon black may vary somewhat depending upon the eiiects it is desired to produce. However, good results are obtained when there is employed between about 2.0 and 3.5% by weight of finely-divided carbon black based on the dry weight of the filament-forming material. There is also incorporated between about 0.001 and 0.03% by weight of finely-divided titanium dioxide based on the dry weight of the filament-forming material. The carbon black and the titanium dioxide may be added to the filament-forming material simultaneously or separately in any desired order. The said pigments may advantageously first be blended with a small proportion of the filament-forming material to form a dispersion and the said dispersion incorporated into the remainder of the filament-forming material.

Once the pigments have been added to the filamentforming material, the latter may be converted into yarn by any desired process such as dry-spinning, wet-spinning, melt spinning, or the like in a manner well known in the art. There is obtained in this manner a yarn having a deep black shade which is well suited for commercial use.

The term yarn is employed herein to cover filamentary materials of all types including, for example, continuous filaments, spun yarns, staple and tow.

The following examples are given to illustrate this invention further.

Example I A spinning solution is prepared by mixing together 63 parts by weight of a 22% by weight solution of cellulose acetate having an acetyl value of 61.6% by weight, calculated as acetic acid, in a solvent mixture containing by weight of methylene chloride and 10% by weight of methanol; 1 part by weight of a dispersion containing 0.3% by weight of titanium dioxide in a solution containing 22% by weight of the cellulose acetate described above in a solvent mixture containing 90% by weight of methylene chloride and 10% by weight of methanol; and 6.4 parts by weight of a dispersion containing 7% by weight of carbon black in a solution containing 7% by weight of the cellulose acetate described above in a solvent mixture containing 90% by weight of methylene chloride and 10% by weight of methanol. A multifilament yarn is produced from the spinning solution by dry spinning.

A spinning solution similar to that described above is prepared from the identical ingredients, with the exception that the titanium dioxide is omitted and the said solution is likewise converted into a multi-filament yarn by dry spinning.

The two yarns are Woven as adjacent warp bands in a fabric and it is found that the yarn containing titanium dioxide has a noticeably deeper black shade as com pared with the yarn containing only carbon black.

Example II A spinning solution is prepared by mixing together 69.5 parts by weight of a 26% by weight solution of cellulose acetate having an acetyl value of 54.5% by weight, calculated as acetic acid, in a solvent mixture containing by weight of acetone and 5% by weight of water; 1 part by weight of a dispersion containing 0.35% by weight of titanium dioxide in a cellulose acetate solution as described above; and 5.9 parts by weight of a dispersion containing 10% by weight of carbon black in a solution containing 10% by Weight of the cellulose acetate described above dissolved in acetone. A multifilament yarn is produced from the spinning solution by dry spinning.

A spinning solution similar to that described above is prepared from the identical ingredients, but omitting the titanium dioxide. The said spinning solution is likewise converted into a multi-filament yarn by dry spinning.

The two yarns are woven as adjacent warp bands in a fabric and it is found that the yarn containing the titanium dioxide has a noticeably deeper black shade as compared with the yarn containing only carbon black.

It is to be understood that the foregoing detailed description is given merely by way of illustration and that many variations may be made therein without departing from the spirit of my invention.

Having described my invention what I desire to secure by Letters Patent is:

1. A pigmented black yarn having incorporated therein carbon black in amount sunicient in itself to make said yarn black and a small proportion, in relation to the amount of said carbon black, of an inert white pigment, the amount of said inert White pigment being sufficient only to give the yarn a deeper black shade as compared with a yarn containing the same proportion of carbon black and no white pigment.

2. A yarn as set forth in claim 1 in which said white pigment is titanium dioxide.

3. A yarn as set forth in claim 2 in which the amount of titanium dioxide is 0.001 to 0.03% based on the weight of the filament-forming material of said yarn.

4. A yarn as set forth in claim 1 in which the yarn comprises an organic ester of cellulose.

5. A pigmented black cellulose acetate yarn having incorporated therein carbon black in amount sufficient in itself to make said yarn black and a small proportion, in relation to the amount of said carbon black, of titanium dioxide, the amount of said titanium dioxide being sufficient only to give the yarn a deeper black shade as compared with a yarn containing the same proportion of carbon black and no titanium dioxide.

6. A yarn as set forth in claim 5 containing about 2 to 3 /2% of carbon black and about 0.001 to 0.03% of titanium dioxide both based on the weight of the cellulose acetate.

7. A spinning solution for the production of pigmented black yarn, said spinning solution consisting essentially of a filament-forming material having incorporated therein carbon black in amount sutficient in itself to make said yarn black and a small proportion, in relation to the amount of said carbon black, of an inert white pigment, the amount of said inert White pigment being suflicient only to give the yarn a deeper black shade as compared with a yarn containing the same proportion of carbon black and no white pigment.

8. A spinning solution as set forth in claim 7 in which said white pigment is titanium dioxide.

9. A spinning solution as set forth in claim 8 in which said filament-forming material is an organic acid ester of cellulose, and the proportion of titanium dioxide is about 0.001 to 0.03% based on the organic acid ester of cellulose.

10. A spinning solution as set forth in claim 8 in which said filament-forming material is cellulose acetate.

11. A spinning solution as set forth in claimv 10 in which the amount of carbon black is about 2 to 3 /2% and the amount of titanium dioxide is about 0.001 to 0.03%, both based on the cellulose acetate.

References Cited in the file of this patent 

1. A PIGMENTED BLACK YARN HAVING INCORPORATED THEREIN CARBON BLACK IN AMOUNT SUFFICIENT IN ITSELF TO MAKE SAID YARN BLACK AND A SMALL PROPORTION, IN RELATION TO THE AMOUNT OF SAID CARBON BLACK, OF AN INERT WHITE PIGMENT, THE AMOUNT OF SAID INERT WHITE PIGMENT BEING SUFFICIENT ONLY TO GIVE THE YARN A DEEPER BLACK SHADE AS COMPARED WITH A YARN CONTAINING THE SAME PROPORTION OF CARBON BLACK AND NO WHITE PIGMENT. 